Vertical tubular mill for fine grinding.



- G. MOREL.

VERTIGAL TUBULAR MILL FOR PINE GRINDING.

\ APPLICATION FILED SEPT. 14, 1910. 1,024,414.

Patented Apr. 23, 1912 piG-B- 2/ m 1 a I 163 3 6?, ff I 4 1 e f 3 fie 5e a 1* {Z l 5' a. e A; l 5 5 5 5 g &T L 1 6 FlG.2.

CHARLES MOREL, OF DOMENE,

ISERE, FRANCE.

VERTICAL TUBULAR MILL FOR FINE GRINDING.

Specification of Letters Patent.

Patented Apr. 23, 1911.2.

Application filed September 14, 1910. Serial No. 582,022.

To all whom it may concern.

Be it known that 1, CHARLES MOREL, residing at Domene, Isere, France, acitizen of the Republic of France, have invented certain new and usefulImprovements in Vertical Tubular Mills for Fine Grinding, of which thefollowing is a specification.

This invention relates toa vertical tubular mill for fine grinding,characterized by an arrangement by which the material to be ground isnot in contact with the balls except in the grinding area, whereby thepower required is considerably reduced as compared with the tubulargrinding mills in which the balls move surrounded by the mass ofmaterial, thus giving rise to very considerable friction, a large partof which is not utilized in the grinding.

The invention is illustrated in the aocom panying drawings, in which-Figure 1 is a vertical section through the axis thereof. Fig. 2 ahorizontal section through 22 in Fig. 1. Fig. 3 is a partial verticalsection, the movable interior platforms and the balls being left as seenfrom outside.

The mill comprises a cylindrical casing a mounted on a base 7), in whichthe driving gear is placed, and which is closed at the top by a cover 0,this form of constructlon enabling the apparatus to be taken to pieceswithout difficulty. In the axis of the cylindrical body thus mounted isa vertical shaft d supported at its lower end by a socket a? andmaintained by bearings (Z at the top and at the bottom of thecylindrical body. On this shaft d superposed platforms 9 are fixed whichform compartments by means of which the balls e are maintained andguided which roll and are applied by centrifugal force to the fixed rimsf adjusted in the cylindrical body a.

The arrangements of the ball-carrying platforms and of the rims f ispeculiar the characteristics thereof which are explained hereafter,insuring the efiectiveness of the grinding.

Each of the platforms 9 comprises a lower part 9 forming a platformproperly speak ing on which the balls lie, and radial parts g formingcompartments of a general triangular shape, for example six in number,as in the drawing. In three of the compartments are placed three ballsand the three others which alternate with the former do not receive anyballs. This number of compartments and of balls might moreover be anyother provided that the total number is even and that the compartmentsalternate as just explained.

In the compartment with balls, the balls are covered by a horizontalwall 9 in such a manner that when the whole device rotates the ballsroll against the track or rim f the material to be ground which fallsat- 03 only arrives in the region of the balls adj acent to the grindingtrack and thus the whole body of the ball is not wrapped in the materialto be ground as would be the case if the upper wall 9 did not exist, andif the material tobe ground could fall over the whole area of thecompartment containing the ball. The result is a considerable reductionin the power required and much less wear.

The compartments not occupied by the balls have an upper surface gslightly inclined from the center toward the periphery. This surfacewhich comes near the grinding track f is intended to receive thematerial to be ground that falls from above and to distribute it alongthe track, where the ball, which arrives soon after, crushes it. Theopenings seen at g are intended to reduce the quantity of metalnecessary for having the surface 9 at a suitable height and the surfaceswhich they form also serve for throwing the material into the grindingtrack.

Between the tracks f and the superposed platforms 9 partitions ordiaphragms i are interposed which have a central opening 2" the objectof which is to regulate the fiow of the material from one stage to theother.

It will be seen from Fig. 1 that these diaphragms are interposed betweenthe lower platform 9 of the upper stage and the upper surfaces 9*, g ofthe lower stage, in in such a manner that the material falling from theupper stage must pass through this central opening z" of the diaphragmin order to reach the stage below. The speed at which the material flowsdepends on the sectional area of this orifice i in the diaphragm, and,consequently the fineness of the grinding can be regulated at will byemploying diaphragms having larger or smaller central openings. Thematerial is conveyed to the upper part of the apparatus by a pipe 7%. Itis conveyed to the first grinding track as explained above; then, itreaches the diaphragm 2' as indicated by the arrows, and pours throughthe central opening 2" in the diaphragm on to the second grinding stage,Where it is conveyed, distributed and ground in the same manner asbefore, and so on to the last stage, whence it is conveyed outsidethrough the p-assagej The transmission of motion to the shaft (Z iseffected by means of two bevel gears 7a 76 arranged in a closed chambercontaining an oil bath formed by the base I) and the shaft Z with itspulleys Z.

This apparatus may of course be constructed with any number of stagesand any number of balls per stage, While the characteristic arrangementsdescribed are still preserved.

hat I claim and desire to secure by Letters Patent is:

1. In a ball-mill for fine grinding, the combination of a verticalcasing, annular grinding tracks and a revoluble shaft therein, stagesmounted on said shaft and provided with radial compartments opening onsaid tracks, alternate compartments having top-closures and containinggrinding balls adapted to roll against said tracks under action ofcentrifugal force, the said remaining compartments of each stage beingadapted to receive and deliver material to said grinding tracks.

2. In a ball-mill for fine grinding, the combination of a verticalcasing, annular grinding tracks and a revoluble shaft therein, stagesmounted on said shaft and provided with radial compartments opening 3 onsaid tracks, alternate compartments having top-closures and containinggrinding balls adapted to roll against said tracks under action ofcentrifugal force .and partitions in each of said remaining com- 4partments adapted to facilitate the delivery to said tracks of materialreceived by each compartment.

3. In a ball-mill for fine grinding, the combination of a verticalcasing, annular 4 grinding tracks and a revoluble shaft therein, stagesmounted on said shaft and provided with radial compartments opening onsaid tracks, alternate compartments having top-closures and containinggrinding balls adapted to roll against said tracks under action ofcentrifugal force, partitions in each of said remaining compartmentsadapted to facilitate the delivery to said tracks of material receivedby each compartment, and diaphragms intermediate said stages havingcentral openings for regulating the fineness of the material ground. Intestimony whereof I have aifixed my signature, in presence of twoWitnesses.

CHARLES MOREL. WVitnesses:

JEAN OHRISTIN, COILLAT LEON.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

